SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '086695e4294bb747a82ffd01609ec1389e217417292fae7050fe8fa9cde47bf3' 
  AND token = 'b2Fku3O+8b2X6BWDh+PfZXIRtJpOn01MYYWOECVaRgE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}